outline exercises class (new attribute of course)

scripts/courses.py

@@ -9,6 +9,7 @@ from config import ROOT, CURRENT_COURSE_ROOT, CURRENT_COURSE_SYMLINK, CURRENT_CO
 from notes import Notes
 from links import Links
 from utils import merge_dictionaries
+from exercises import Exercises
 
 
 class Course:
@@ -32,6 +33,7 @@ class Course:
         self.info = merge_dictionaries(self.info, fallback_file)
         self._notes = None
         self._links = None
+        self._exercises = None
 
     @property
     def links(self) -> Links:
@@ -45,6 +47,12 @@ class Course:
             self._notes = Notes(self)
         return self._notes
 
+    @property
+    def exercises(self) -> Exercises:
+        if not self._exercises:
+            self._exercises = Exercises(self)
+        return self._exercises
+
     def __eq__(self, other):
         if other is None:
             return False

scripts/exercises.py

@@ -0,0 +1,78 @@
+from file_list import Files
+from pathlib import Path
+from typing import Dict
+
+
+class ExerciseWriteUp:
+    def __init__(self, root_dir: Path, course):
+        self.root_dir = root_dir
+        self.course = course
+        self.number = 1
+
+    def edit(self):
+        pass
+
+
+class Exercise:
+    def __init__(self, course, number: int):
+        self.course = course
+        self.number = number
+        self._writeup = None
+        self._problem = None
+        self._solution = None
+
+    @property
+    def writeup(self):
+        if not self._writeup:
+            self._writeup = next((w for w in self.course.writeups if w.number == self.number), None)
+        return self._writeup
+
+    @property
+    def problem(self):
+        if not self._problem:
+            self._problem = next((p for p in self.course.problems if p.number == self.number), None)
+        return self._problem
+
+    @property
+    def solution(self):
+        if not self._solution:
+            self._solution = next((s for s in self.course.solutions if s.number == self.number), None)
+        return self._solution
+
+
+class Exercises(list):
+    def __init__(self, course):
+        self.course = course
+        self.info: Dict = course.info['exercises']
+        self.root: Path = course.path / self.info['path']
+        self.sheet_root = self.root / self.info['sheets'].strip()
+        self.solutions_root = self.root / self.info['solutions'].strip()
+        self.root.mkdir(parents=True, exist_ok=True)
+        self.sheet_root.mkdir(parents=True, exist_ok=True)
+        self.solutions_root.mkdir(parents=True, exist_ok=True)
+        self._solutions = None
+        self._writeups = None
+        self._sheets = Files(self.sheet_root)
+        list.__init__(self, (Exercise(self.course, num) for num in map(lambda s: s.number, self._sheets)))
+
+    @property
+    def sheets(self):
+        return self._sheets
+
+    @property
+    def solutions(self):
+        if not self._solutions:
+            self._solutions = Files(self.solutions_root)
+        return self._solutions
+
+    @property
+    def writeups(self):
+        if not self._writeups:
+            dirs = (d for d in self.root.iterdir()
+                    if d.root is not self.sheet_root.root and d.root is not self.solutions_root.root)
+            self._writeups = sorted((ExerciseWriteUp(d, self.course) for d in dirs), key=lambda e: e.number)
+        return self._writeups
+
+    def read_write_up_dirs(self):
+        dirs = self.root.iterdir()
+        return sorted((ExerciseWriteUp(d, self.course) for d in dirs if d is not self.sheets), key=lambda e: e.number)